Skip to main content

Full text of "Contagious abortion in cows"

See other formats

I yv 

UNIVERSITY OF CALIFORNIA agricultural Experiment Station 




(June, 1903.) 



Director of the New York State Veterinary College, Cornell University, Ithaca, N. Y. 

Introductory Note. — Frequent applications to the Agricultural Experiment Station 
of the University of California for information concerning contagious abortion in cattle, 
indicate that the disease is a serious one in California, as is true in other dairy regions of 
the United States and Europe. In response to these frequent demands for aid, the fol- 
lowing article, by an acknowledged eminent authority, is presented. The Agricultural 
Experiment Station is deeply indebted to Dr. Law for his generous permission for the 
reprinting of this product of his pen. The control of contagious abortion is a trouble- 
some matter, requiring the exercise of numerous precautions, the neglect of any one 
of which may nullify all previous efforts. Dr. Law has achieved marked success, by 
the methods to be hereinafter mentioned, among animals quite closely restrained as in 
the dairies of New York State. The article was written with reference to Eastern con- 
ditions, and doubtless some of his suggestions may require considerable modification 
to fit California practice. 

ARCHIBALD R. WARD, Veterinarian. 


Cows are liable to abortion from a great variety of causes, some of 
which, like mechanical injuries, are purely individual to the animal and 
show little tendency to extend to other members of the herd. Other 
forms attack a considerable proportion of the herd at the same time, or 
in succession, and thus appear as if they partook of a contagious char- 
acter. In many such cases, however, the implication of a number of 
pregnant cows in the same herd is only a common result of a special 
injurious condition, to which all are alike exposed, and the removal of 
this is the signal for the disappearance of the disease. Thus unwhole- 
some food of all kinds which undergoes fermentation in the first 
stomach, causing the accumulation of gas (bloating), will at times cause 
a widespread abortion. The consumption of ice-cold water usually stimu- 
lates the womb to contraction and the unborn calf to active movements, 
which can be easily observed in the right flank. This, frequently 
repeated or carried to excess in susceptible animals, will at times cause 

abortions. The consumption of irritant vegetables, which have a 
special tendency to act on the kidneys or womb, are causes of general 
abortions in herds. 

Ergoted grasses have long been known as causes of abortion, and the 
same remark applies to smut and several other fungi. It is true that 
these cryptogamic vegetable products vary much in their character and 
strength according to the variations of the season and the local condi- 
tions under which they grow, as well as the time or stage at which they 
are harvested, so that the ergots and smuts of one year appear to be 
comparatively harmless, while those of another year or season or 
locality are very injurious. The fact remains, however, that under 
given conditions of growth they are unquestionably causes of abortion, 
and in such cases the abortions are widespread in the herd or in differ- 
ent herds in the same district. Cases such as these are easily mistaken 
for contagious ones, though there is in the system of the aborting 
animal no self-propagating germ which would produce the disease if 
transferred to another animal. 

Still other conditions may produce widespread abortions in the 
absence of any specific contagious germ. On the magnesian limestones 
of New York, cows are very subject to small stones in the kidneys dur- 
ing the dry feeding of winter, and when this is added to other existing 
causes, like the riding of cows in heat, attacks made with the horns of 
their fellows, squeezing in half-closed gates, over-driving, sloping stalls, 
or too laxative food, abortions are likely to be induced. In other sus- 
ceptible animals the proximity to a slaughter-house, the sight and 
smell of dead carcasses, or carrion, etc., will excite a pregnant cow to 

The Contagious Form. — Any of the usual causes of sporadic or 
accidental abortion may co-exist with the true contagious element and 
give unusual energy to it, yet it is of the utmost importance to identify 
the contagion in all cases in which it is present as the essential cause. 
This can usually be done by a careful inquiry into the history of the 

When a herd has been continuously healthy up to the time of the 
introduction of a cow brought from a herd where abortion has been 
prevailing, and when, following her advent, one and another and another 
of the original numbers of the herd abort, without any apparent cause 
in the way of change of feed, water, barn, stalls, or general management, 
the evidence of the introduction of the element of contagion by the cow 
in question is very circumstantial and forcible. If pregnant cows 
standing next to the new cow, or near to her, are among those that early 
abort, the argument for contagion is still further corroborated. If the 
trouble continues in the herd year after year, attacking fresh animals 
some months after purchase, the case becomes still stronger. 

Or take another case. A cow is sent from a herd to be served by a 
bull which has been allowed to serve an aborting cow, and her resulting 
pregnancy is terminated by abortion before the regular time, and this 
is followed by successive abortions by different animals in the previously 
healthy herd. Upon the face of it, an outbreak of this kind is mani- 
festly contagious, and in the absence of any other appreciable cause for 
the trouble, it may be safely held to be so. 

Or, a bull is brought from a herd where abortions have taken place, 
and after his arrival the cows begin to abort, the first cases being in 
those which the new bull has served. The occurrence is manifestly due 
to contagion. 

Or. a newly purchased cow aborts and is disposed of in consequence, 
and another cow, placed in the same stall, in due time aborts also, and 
others follow in due time, especially those that stood next to or near to 
this stall. Everything points to an introduced contagion. 

Such indications might be varied indefinitely; all variations, however, 
having the one thing in common, that the evidence of infection stands out 
prominently and unmistakably. The infection may have been evidently 
carried by the tail, tongue, soiled stall, litter, gutter, rubbing post, fence, 
or other object, yet the fact of contagion can be demonstrated with 
reasonable certainty. 

These conclusions have been repeatedly affirmed by actual experi- 
mental transmission. The Scottish Abortion Commission found that 
healthy, pregnant cows often escape, though standing near to an aborting 
cow, but that when a piece of cotton wool Avas inserted in the vagina of 
the aborting cow for twenty minutes, and was then transferred to that 
of the healthy one, the latter invariably aborted. Galtier found that 
the infecting vaginal mucus of the aborting cow, when transferred to 
the same passage in other animals, caused abortion in the sow, ewe, 
goat, rabbit, and guinea-pig; whilst if it was intensified by passing 
through the rodents, it would similarly affect the mare, bitch, and cat. 

Bang subjected two cows, which were three months pregnant and had 
come from healthy herds, to repeated vaginal injections, with the 
products of culture of the abortion bacillus in serum-glycerine-bouillon. 
Three injections were made on April 14th, May 23d, and June 4th, and 
on June 24th one cow aborted. The other was ill, and when killed she 
was found to carry a dead foetus. Pure cultures of the abortion bacillus 
were found in foetal membranes and liquids of both animals. 

Casual Infections. — In a case which came under the observation of 
the writer recently, a family cow, kept in a barn where no abortion had 
previously occurred, was taken for service to a bull in a herd where 
abortion was prevailing, and though she was only present at the latter 
place for a few minutes, she aborted in the sixth month. 

_ 4 — 

Another cow, from the same aborting herd, was taken into another 
herd at a distance of about two miles, and where abortion had been 
unknown up to that time, and some months later a cow standing in the 
next stall to her aborted. The remainder of this herd was sold soon 
after, so that the further progress of the disease could not be easily 

Jansen, as quoted by Sand, reports the case of a cow from an aborting 
herd having been taken into a herd that had been previously quite free 
from the disease. Soon after her arrival she aborted, and later cow after 
cow of the original herd aborted. The owner kept the matter secret, 
and sent his cows to a neighbor's bull for service, with the result that 
for two years abortion prevailed among cows served by this bull. 

Tobiassen quotes the case of a cow in an aborting herd, which calved 
a fortnight before the regular time. The calf was at once sent to 
another farm where no abortions had occurred, and placed in the same 
building with the pregnant cows, all of which later aborted. The out- 
break thus started lasted for several years. 

J. R. Jansen reports that a cow brought from an infected farm, for 
fattening purposes, proved to be pregnant and finally aborted, and that 
twenty-four of the pregnant cows on the farm aborted in the same year. 

Morck reports that a cow which had aborted a fortnight previously 
was taken to a farm where abortions had never been known. She 
aborted during her next pregnancy, and so did all of the herd, nine in 

Christensen records the occurrence of a general abortion in a pre- 
viously healthy herd, members of which had been sent for service to 
the bull of a neighboring aborting herd. 

Uygaard reports that a bull from a healthy herd, but which had been 
allowed to serve some cows from a neighboring infected herd, was sold 
to go on a previously healthy farm, where he was put to fourteen cows 
only. Of these, twelve aborted; while the other cows, served by another 
bull, remained well. 

Cases like the above are not to be explained by some imaginary 
unwholesome conditions of the environment, since in every instance 
the surroundings of the animals and the conditions of life remained 
the same, and the only appreciable cause of the outbreak in every case 
was the contact with an animal from an aborting herd. 

Experimental Infections. — Any possible doubt, however, may be re- 
moved by the cases of experimental transmission of the disease, by the 
transference of the mucus from the vagina of an aborting cow to the 
vagina of a healthy pregnant one. The experiments of Bang have 
been already quoted. 

The Scottish commission (Woodhead, McFadyean, and Atkin) took 


— 5 — 

a pregnant cow from a healthy herd and placed her in a stable where a 
large number had aborted. They also inserted into the vagina of this 
cow a plug of cotton wool, which had been left for twenty minutes in 
the vagina of a cow which had recently aborted. This was repeated the 
next day, the plug being left in the vagina for several hours on each 
occasion. Within a month some indications of a threatened abortion 
showed themselves, and a seven months' calf was dropped on the seven- 
tieth day after the inauguration of the experiment. 

In a second experiment, a cow six months in calf and taken from a 
healthy herd was placed in a stable with an aborting herd and a quan- 
tity of vaginal mucus from a cow which had recently aborted was 
injected under the skin of the vulva. She calved prematurely at the 
end of the eighth month. 

Williamsen when treating a herd for abortion took a piece of the after- 
birth of an aborting cow and rubbed it on the vagina of a healthy cow 
of his own, which had a habit of carrying her calf fourteen days over- 
time. Five days after she had premature parturition. He took a frag- 
ment of the foetal membrane from the cow just named and rubbed it on 
the vagina of a pregnant cow, condemned to slaughter for tuberculosis. 
In seventeen days the cow aborted. 

Abortion Germ. — A number of investigators have sought assiduously 
for the germ of abortion. More than twenty years ago Franck attrib- 
uted the disease to loptothrix vaginalis, a spherical organism united in 
chain form. 

The Scottish Abortion Commission isolated no less than five different 
bacteria from the abortion membranes and vaginal mucus, but failed to 
identity any one of these as the essential cause of the disease. 

Nocard found in the fibrino-purulent matter between the chorion and 
womb, in aborting animals, two different organisms, a micrococcus 
(globular microbe) isolated or united in chains of two or three, or more, 
and a short, thin bacillus (rod-shaped microbe) isolated or attached 
together in pairs. These he did not find in healthy pregnant cows. 
They seemed to have no evil influence on the animal in the intervals 
between pregnancies, so he concluded that they caused disease of the foetus 
and foetal membranes alone and did not affect the womb of pregnant ani- 
mals. He allows, however, that the germ can survive in the unimpreg- 
nated womb until the next pregnancy, and may thus be kept up for 
years in the same animal. 

Galtier, on the other hand, has conveyed the disease by feeding and 
inoculation of the milk or abortion membranes, to the sheep, goat, pig, 
rabbit, and guinea-pig, and claims accordingly that the disease is one 
affecting the general system of the pregnant animal and that the germs 
can be conveyed through the blood to the womb. He claims that the 

— 6 — 

germ is intensified in force by passing through the body of the rabbit 
or guinea-pig, and can then infect horses, dogs, and cats. 

Chester, of the Delaware College Agricultural Experiment Station, 
found in the placentas of aborting cows a bacillus, which in form and 
habit of growth closely resembled the common bacillus of the large 
intestine (Bacillus coli communis) . In the fermentation test, however, 
it showed a marked difference from the colon bacillus, to which it seems 
to be so closely allied. Inoculated on rabbits it was not fatal. Injected 
into the vagina of a pregnant cow, it caused slight discharge for four or 
five days, but the calf was carried to full time — six and one half months 
after the injection. 

Bang found in aborting cows, between the womb and the foetal mem- 
branes, a considerable odorless liquid exudate of a gelatinoid appearance, 
and some pus cells. There w T as active catarrh of the mucous membrane 
of the womb, which continued after abortion and often maintained the 
disease into the next pregnancy. In the exudate was an abundance of 
very small bacilli, which stained deeply with aniline colors, excepting 
in a vacuole or nucleus which was less highly colored. This bacillus 
grew well in serum-glycerine-bouillon, and more sparingly in serum- 
gelatin-agar. In the latter, it showed a remarkable peculiarity in 
growing with special luxuriance in different zones at two separate 
depths, beneath the surface, while there was an intervening clear space 
in which little or no growth took place. This preference for two differ- 
ent grades of abundance of atmospheric air and rejection of the inter- 
vening grade serves to identify the bacillus in a very striking manner. 
Injected into the vagina in two pregnant cows from healthy herds it 
produced abortion in one on the twenty-first day, and death of the calf 
without prompt abortion in the second. It also induced uterine catarrh 
and abortion in ewes, rabbits, guinea-pigs, and mares, when it was 
injected into the vagina. In several cases in which it was injected 
under the skin or into the veins, it was later found in abundance in the 
interior of the womb and the foetal membranes and bowels of the foetus. 
It can therefore live in the blood and pass from that to the womb to 
start its baneful work there. 

Dr. V. A. Moore and the present writer have made a series of experi- 
ments at the New York State Veterinary College. We have found in 
the foetal membranes and uterine mucus of a number of aborting cows, 
in different counties of the State, and situated widely apart from each 
other, a bacillus which in form and culture-experiments closely 
resembles Bacillus coli communis. This was nearly always found in 
pure cultures; in a few cases only were other microbes found, and these 
only such as are found in a healthy vagina. It was never found in the 
foetal membranes, nor in the mucus of the womb in cows which had 
come to the period of parturition in healthy herds. It agreed in most 

respects with the bacillus found by Chester, but differed somewhat in 
fermentation tests. It differed also in being fatal to rabbits when 
inoculated on these animals. Injected into the vagina of three preg- 
nant cows, it continued to live on its lining membrane, producing more 
or less catarrh and mucopurulent discharge in the different cases, yet 
all three carried their calves to the full time as judged by the forward 
condition of the teeth, one having calved on the 123d day, the second 
on the 167th, and the third on the 190th after injection. 

The investigations at the Delaware College Experiment Station and 
the New York State Veterinary College indicate that the contagious 
abortion which was met with in the cows of these States is essentially 
different from the forms studied in Europe by Nocardand Bang, respec- 
tively. The facts that thesame germ was found alone or, exceptionally, 
along with the normal microbes of the healthy vagina in the womb of 
every aborting cow, and that it was not found in the healthy cow which 
had calved at full time, and that the generative passages were the seat 
of a catarrh, alike in the cows that aborted and in those that were 
injected with cultures of the germ found in the womb of the aborting 
animal, are virtually all but conclusive that this microbe is the essential 
cause of the abortion. 

The fact that abortion has not so far occurred in the pregnant cows 
injected experimentally with the artificial cultures of this germ, only 
serves to show that under certain conditions the microbe operates 
slowly. In our cases the cows were dry during nearly the whole course 
of the experiment, and stood quietly in stalls, so that there was little 
accessory cause to assist in precipitating abortion. It is further worthy 
of note that in the form of abortion habitually prevalent in New York, 
it is the rule rather than the exception that the period of incubation 
often extends to the sixth month. In a recent case which came under 
the observation of the present writer, and in which the cow contracted 
the infection by the service of a bull in a neighboring aborting herd, the 
abortion took place at the sixth month of pregnancy. In our experi- 
mental cases, it was certain that the same bacillus, which was alone 
found in the aborting womb and which was present there in great 
abundance, remained present in the generative passages of the infected 
animals up to the time of parturition and thereafter. 

It is worthy of notice that the recent bacteriological investigations of 
the disease in Europe show that the pathogenic germ is present in large 
numbers in the digestive organs of the calf, that the new-born calf can 
convey the disorder into a fresh herd (Sand), and that the viable calves 
of infected cows are liable to die from intestinal disorders a few days 
after birth. Galtier, the Marquis de Poncius, and Pry insist strongly on 
this. On a farm on the estate of the Marquis, where abortion has pre- 
vailed for over twenty years, calves of infected cows show at birth or 

very shortly after symptoms of broncho-pneumonia and of a complica- 
tion of nervous disorders. They are breathless, wheeze, discharge from 
the nose, cough, scour, have convulsions and other nervous troubles. 
A large proportion of such calves die, and their lungs are found in 
part red, consolidated and destitute of air, while the air tubes contain a 
mucopurulent liquid. Lesions denoting inflammation of the pleural 
covering of the lungs, of the liver, and of the intestines are common. 

This coincidence of a fatal disease in many of the surviving calves has 
not been specially noticed in the aborting herds in New York. Should 
it be found to be wanting or infrequent, it will establish still another 
distinction between the European abortions, as noticed by Nocard, 
Galtier, Bang, and others, and the American type, as observed in 
Delaware and New York. 

In investigating this subject it must be borne in mind that any 
catarrhal condition of the mucous membrane of the uterus hinders con- 
ception, and becomes a direct cause of abortion, and that the forms of 
invasion of the womb by pus-producing germs are as numerous as the 
number of different irritant germs that can live in the membrane. The 
question as to how many of these may induce contagious abortion is to 
be determined by the susceptibility of the membrane to the attack of 
each particular germ, and whether the latter can retain all its power of 
survival and virulence in passing from one animal to another. The 
presumption is, therefore, in favor of a variety of forms of contagious 
abortion, each due to its own specific microbe or microbes rather than 
of a single unvarying type of the disease. It is the work of the future 
investigator to demonstrate the extent and nature of such variations, 
and to place the diagnosis and treatment of each on a substantial basis. 

The indication that there are probably at least two forms of contagious 
abortion in cows raises the question whether both are to be found in 
our American herds, and, if not, whether there is not an urgent demand 
for such a rigid quarantine and inquiry into the condition of all 
imported cattle as will establish a reliable barrier against the more 
dangerous foreign disorder? No less impoitant is it that we should 
recognize the presence of the more dangerous disease, if it should 
already have a foothold in American herds, and trace its cause, nature, 
and diagnostic symptoms, so that the treatment appropriate to each 
individual outbreak may be promptly and intelligently applied. The 
tens of thousands of dollars lost every year through the prevalence of 
contagious abortions in the dairy herds of New York would justify a 
liberal outlay to establish our knowledge and practice on a rational and 
scientific foundation. In Europe the loss on each aborting cow is set 
at from $12 to $25 per annum. 

Do the Same Animals Abort Several Years in Succession? — The ques- 
tion of persistent abortion, year after year, by the same cow, is one of 

— 9 — 

far-reaching importance. If a first contagious abortion entails a second, 
a third, a fourth, and a fifth in the same animal, in as many successive 
years, then manifestly her preservation is a mere squandering of money, 
apart from the danger of her transmitting the disease to other and 
healthy animals. If, however, on the other hand she herself fails to 
abort the second or the third year, yet if she continues to carry in her 
generative passages the germs of the malady, as potent as ever for evil 
to other pregnant cows, her preservation in her present condition is a 
hidden source of the infection, that can still spread from her to all new 
and susceptible cows which may be added to the herd. 

It was long supposed that repeated abortion for an indefinite number 
of successive years was inevitable in the animal which was once 
infected. There is no doubt that certain cases give color to this belief. 
In an organ so nervously susceptible as the womb, there is always a 
tendency to repeat the abortion under the stimulus of a new pregnancy 
and the gradual distension and development of the uterine walls. Yet 
statistics show that this only applies to a small proportion of cows, and 
these the most excitable and nervous. The tendency toward insuscep- 
tibility to the deleterious action of the germ, which still may be present, 
is in the cow greater as a rule than the disposition toward a nervous 
increase of the susceptibility. The difficulty in reaching a conclusion 
on this point depends on the fact that stock-owners very commonly dis- 
pose of aborting cows, and as the freshly bought cows are sooner or 
later attacked, it is too confidently assumed that the old cows, too, 
would have aborted had they been retained. Many years ago observant 
New York dairymen had noticed that the same cow rarely aborted over 
three years in succession and the majority not over two. Quite recently 
the owner of a large herd, who had had much experience with the 
disease, assured me that the rule was that a cow did not abort a second 
time. The continuance of abortion in the herd was mainly among 
newly purchased cows, and others that had not been previously attacked. 
The same is measurably true of the European abortions. Nocard says 
that after three to five years there is an acquired immunity. Penberthy 
says that in case of repeated abortion in the same cow, the calf is 
carried longer each successive year until it comes to its full term. 
Sand, in his symposium of the experience of Danish veterinarians, 
says it is quite exceptional that a cow should continue to abort, but 
outbreaks of abortion disappear spontaneously if no new cows are 
brought in. 

In the main this is indorsed by the experience of Bang. In a herd 
of two hundred head, in the course of several years, eighty-three aborted 
in their first pregnancy, and of these only twenty aborted in the second, 
and seven failed to breed. Counting these latter as having aborted, 
this amounted to less than one third, while over two thirds of the cows 

— 10 — 

which aborted the previous year carried the calf the full time. In the 
herd, only thirty aborted for two successive years, and only six for three 
years running. 

Paulsen quotes the case of a herd of sixteen, seven of which were sent 
for service to a bull in an aborting herd. All seven aborted: five at 
ten weeks, one at three months, and one at four and a half months 
before the normal period of parturition. One of the seven was sold, but 
the remaining six went full time in the following year. 

Morck records the case of a herd of sixteen cows, of which the majority 
aborted the same year. The owner disposed of all the aborting animals 
and replaced them by others freshly purchased. Next year the new 
stock aborted, together with some of the cows that had been held over. 
He continued this course for eight years without any improvement, and 
then decided to keep the aborting cows, as well as the others. In two 
years the affection disappeared from the herd. 

Such small herds, in which all become early infected, and in which 
there are not yearly additions of young animals in their first pregnancy, 
nor the opportunity for a continuous extension into new animals that 
have previously escaped infection, furnish a better opportunity than do 
the larger herds, to trace the acquirement of artificial immunity. 


Admitting the frequency of acquired insusceptibility, we have to 
guard more against repetition of abortion in the same cows. To protect 
the new stock against infection, however, it becomes necessary to purge 
from the infection all cows which still harbor the germ in their genera- 
tive passages, though they do not themselves any longer abort. It also 
becomes necessary to guard against infection through stalls, bulls, etc., 
from such infected, but no longer aborting, cows. 

The following was written with reference to conditions in New York 
State, and portions of the suggestions are inapplicable to cattle upon 
the ranges in California. 

Upon the following there can be no dispute: 

First — The cow which shows symptoms of abortion should be at once 
removed from the others, and her stall, including the gutter and drain 
leading from it, thoroughly disinfected. 

Second — Every cow which has aborted should be instantly removed 
from the stable into a separate building, and her stall, with its gutter 
and drains, thoroughly disinfected. 

Third — The aborted foetus, with its membranes, should be at once 
removed and burned or boiled, or deeply buried after it has been 
sprinkled with chlorid of lime or other active disinfectant. 

— 11 — 

Fourth — The manure from the infected stable should be taken into 
an inclosure to which no cows have access, and freely watered with a 
solution of sulfate of copper (one ounce in one quart of rain water). 

Fifth — The cow which has aborted, and those standing on each side 
of her, should have the external generative organs, the adjacent parts 
of the thigh, and the whole length of the tail sponged every morning 
with the solution of one ounce of sulfate of copper in one quart of 

Sixth — The cow that has aborted or is suspected of abortion, and 
which has been isolated from the herd in a special stable, should have 
its stall carefully cleaned, scraped, and watered daily with the sulfate 
of copper solution. Her manure and urine must be carefully disin- 
fected, as provided above. 

Seventh — In case that more than one animal has aborted in a herd 
or stable, it is desirable to sponge the external generative organs, hips 
and tails of the whole herd daily with the sulfate of copper solution, 
and to disinfect the hind parts of the stalls, the gutter, and the drains 
every morning, as prescribed above. 

Eighth — Further to prevent the introduction of the infection into a 
herd, all newly-purchased cows should be put at first in a separate quar- 
antine stable, and be subjected to daily disinfection of the external parts, 
and the stalls. As each cow comes in at full time, and without any 
further indication of disease, she may be transferred to the stable 
occupied by the general herd. 

Ninth — In purchasing a bull the greatest care must be taken to see 
that he comes from an absolutely sound herd, and that he had not been 
allowed to serve cows from a herd where abortion exists. It is a safe 
precaution to wash his sheath with the disinfectant liquid and to inject 
it freely with the same before beginning to use him in the herd. He 
should be allowed to serve no cows from outside the herd, unless it can 
be shown that they are from herds that are absolutely free from abortion. 

By a rigid application of the above measures the extension of conta- 
gious abortion in a herd can be certainly prevented, and the rule being 
that the majority do not abort a second time, the disease can in this way 
be got rid of. 

It must be borne in mind, however, that in an infected herd there will 
always be a certain number of pregnant animals, in which the germ is 
alw r ays lodged deeply in the vagina and even in the womb, and these 
measures can not prevent the occurrence of abortion in their cases. 
There is also the danger in a certain limited number of those which 
have a tendency to abort a second time, that the germ will continue to 
live throughout the following year in the interior of the womb, and not 
only cause another abortion in the individual cow, but start the infec- 
tion anew in other members of the herd. 

— 12 — 

There is some danger of such survival even in a cow which has become 
herself immune so that she will carry her calf to full time and yet infect 
other susceptible cows which may be exposed more or less directly to 
her discharges. It is for such cases that medication by the mouth and 
injections into the vagina or womb have been resorted to. 

Tenth — Among medicines used to check abortion by acting on the 
general system are viburnum prunifolium and potassium chlorate, which 
can hardly be upheld as disinfectants, but act only on the nervous sys- 
tem or on the general health. Carbolic acid, one of the latest fads, is 
employed, on the other hand, with the intent of checking the propagation 
of the contagious element. Diluted in water so as to be non-irritating, 
it has been injected daily under the skin, for a length of time and with 
alleged good results. It is noticeable, however, that when the good 
effects have been apparently most constant the animals have at the same 
time been subjected to very careful and continuous external disinfection, 
which in itself is amply sufficient to account for the favorable applica- 
tions, the results have been much less favorable. Thirty-seven Danish 
veterinarians employed it in ninety-two separate herds, with results 
that were apparently good in forty-seven cases, doubtful in twenty, and 
negative in twenty-five. Thirteen other veterinarians who have em- 
ployed it extensively report the results as doubtful or negative. It is 
not surprising that a majority of these practitioners abandoned a method 
which in theory must be looked on as unpromising and which proved so 
uncertain in actual practice. 

Eleventh — The other resort is a priori more promising, consisting as 
it does in the application of a disinfectant to the infected mucous mem- 
brane of the generative organs. The two agents most in use are carbolic 
acid and mercuric chlorid. 

Carbolic acid, which is the less dangerous agent, is prepared by add- 
ing one troy ounce and a half of the acid to a gallon of water, together 
with a troy ounce of carbonate of soda. This is injected daily for a 
week, through a large syringe, or an elastic rubber tube introduced into 
the passage and having a funnel inserted in its outer end, which is 
carried two feet higher than the root of the tail. A quart may be 
employed at each injection and it should be used milk-warm. 

The mercuric chlorid, the more poisonous of the two agents, is used 
in a solution of one drachm to the gallon of water, to which is added a 
drachm of hydrochloric acid. This is used milk-warm in the same way 
as the carbolic acid solution. This is very corrosive as well as poison- 
ous, and must be kept in a wooden vessel, safely locked up from man 
and animals. 

The writer has used such injections in aborting animals and herds, 
and at the same time with the daily disinfection of the external parts 

— 13 — 

of the generative organs, the stalls, gutters, drains, and manure, and 
with perfect success where it could be thoroughly carried out. 

It is subject to the serious objection that it causes active straining 
when the injection is administered, and if this becomes extreme, it may- 
create apprehension that it will precipitate abortion rather than obviate 
it. This has led Nocard and others to abandon the injections and to 
rely altogether on external disinfectants. For pregnant animals this is 
to be commended, as the disinfectant can not penetrate and disinfect an 
already infected womb, and is therefore not likely to prevent an abor- 
tion when the germ has already gained that cavity. In the cow that 
has just aborted, on the other hand, the danger of injury from this 
cause is reduced to the minimum, and the disinfectant injection, thrown 
into the depth of the womb itself, offers the only hope of a speedy dis- 
infection of that cavity. The external application merely prevents the 
access of new germs from without, while those that are within are left 
to be destroyed by the unaided action of the lining membrane of the 
womb. That this action is usually slow is illustrated by the fact that 
abortion germs habitually live for a length of time in the vagina and 
womb, before producing abortion, and that they often continue to live 
there much longer unless preventive measures are resorted to. In the 
animal which has aborted some time before and which is still unim- 
pregnated, injections are equally commendable. It may not be admis- 
sible in this case to introduce the liquid into the womb, but even if 
limited to the vagina, the resulting disinfection is highly advantageous 
in cutting off this source of renewed infection for the uterus, and placing 
the organ in a much more favorable position for the destruction of the 
bacilli which it contains. 

Conclusion. — In conclusion, it may be stated that this subject still 
offers an extensive field for profitable investigation, and that we should 
not rest satisfied with the partial knowledge already attained, but push 
our inquiries in new directions when there is a good prospect of securing 
the means of a fuller, more perfect, and more easily available control of 
this great source of loss to our dairy interests. The form or forms of 
contagious abortion in our home herds should be fully investigated and 
the conditions of the life and propagation of the germs more definitely 
determined, and the same should be secured for other forms which may 
not as yet be indigenous to the United States, but which are likely to 
be introduced through the medium of importations. Our dairy industry 
is one of the most important of our sources of income, and a moderate 
outlay for an investigation which will render that safer and more 
remunerative, or which will protect it against threatened dangers from 
without, must prove an important measure of natural economy. 


1 903. 

I ' \